The usually present wind-and-weather shields on motorcycles do to some degree protect radios mounted closely behind such shields. And while it would be obvious to place a completely covering protective box or bag over the radio in bad weather or when not in use, there is a need for a protective box which would for most of the time permit normal (adjustable) use, but which would provide complete covering when needed or desired. It is the principal object of this invention to provide such a cover.